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Biomedical subjects

R Gonzalo

Publications and source records attributed to R Gonzalo.

4 recordsLinked to original sources
PubMed2003

Splicing mosaic of the myophosphorylase gene due to a silent mutation in McArdle disease.

The authors report the molecular findings in a patient with McArdle disease who harbored a silent polymorphism (K608K) in the myophosphorylase gene. cDNA studies demonstrated that this polymorphism leads to a severe mosaic alteration in mRNA splicing, including exon skipping, activation of cryptic splice-sites, and exon-intron reorganizations. These findings suggest that, in patients with McArdle disease in whom no pathogenic mutation has been found, any a priori silent polymorphism should be re-evaluated as a putative splicing mutation.

Alternative Splicing↗
PubMed1982

Application of electronically differentiated high-performance thin-layer chromatographic densitograms to the assay of some preservatives used in pharmaceutical formulations.

The results of an extended study on the feasibility and scope of derivative high-performance thin-layer chromatography (HPTLC) for the assay of unresolved components are presented. It is shown that as the resolution decreases the accuracy of quantitative digital electronic integration, area and peak height measurements diminish to a point where the differentiated signal becomes the only valid approach to the direct quantitation of unresolved HPTLC spots. Using the first derivative, the accuracy of these assays can be maintained within 2-3%, independently of the resolution, and the derivative techniques provide a very useful alternative to direct HPTLC analysis of small amounts of a component masked by major peaks. In practice, this simplifies the optimization of experimental parameters in HPTLC, and results in shorter analysis times. The HPTLC spots are estimated in a spectrophotodensitometer, the signal of which is electronically differentiated by means of an analog circuit, capable of recording the first or second derivative spectrum. Instrumental possibilities for optimizing and enhancing the differential signal are discussed.

Chemistry, Pharmaceutical↗
PubMed1980

Derivative and graphical procedures for correction of irrelevant UV spectrophotometric absorption in changeable matrixes.

The application of direct zero-order UV spectrophotometric and graphical or derivative background correction methods to selected pharmaceutical preparations shows their relative advantages in different situations. The assay of the active components in a changeable matrix is a problem with formulations having a limited shelflife. Although the standard three-point correction procedures can provide accurate data, there are practical problems if the irrelevant absorption band is such that only the derivative approach gives enough resolving power for reliable qualitative and quantitative determinations.

Chemistry, Pharmaceutical↗